Having driven various C Class models over the last two years I'm afraid I didn't recognise any of the negatives that Dojj mentioned.

I can regularly get 60+ on a run in my current C200 (only 136hp), but my C220s could nudge 60mpg. I've never had one return less than 47mpg over 5,000-9,000 miles and that includes a lot of city driving as well as motorways and extra-urban stuff.